采后跃变型果实软化与果胶降解的研究进展  

Research progress on postharvest fruit softening and pectin degradation in climacteric fruits

作　　者：高华奇 王立芹 孙翠 黄凌霞[1,4] GAO Huaqi;WANG Liqin;SUN Cui;HUANG Lingxia(Institute of Applied Biological Resources,Zhejiang University,Hangzhou 310058,Zhejiang,China;Linyi Forestry Bureau of Shandong Province,Linyi 276001,Shandong,China;Institute of Fruit Science,Zhejiang University,Hangzhou 310058,Zhejiang,China;Rural Development Academy,Zhejiang University,Hangzhou 310058,Zhejiang,China)

机构地区：[1]浙江大学应用生物资源研究所,杭州310058 [2]山东省临沂市林业局,山东临沂276001 [3]浙江大学果树研究所,杭州310058 [4]浙江大学新农村发展研究院,杭州310058

出　　处：《果树学报》2022年第10期1922-1934,共13页Journal of Fruit Science

基　　金：浙江省“十四五”农业新品种选育重大育种专项蚕桑协作组项目(2021C02072-5);国家重点研发计划(2017YFE0122300);浙江省基础公益研究计划项目(LGN21C200016);浙江省蚕蜂资源利用与创新研究重点实验室(2020E10025)。

摘　　要：呼吸跃变型果实采后会在出现呼吸高峰后迅速成熟衰老软化,影响其营养价值与商品价值,而造成其软化的现象与细胞壁果胶的降解相关。笔者在本文中结合国内外最新研究进展,介绍了水果细胞壁中果胶的组成及其分子结构,综述了水果软化过程中水溶性果胶(WSP)、离子可溶性果胶(ISP)和共价可溶性果胶(CSP)等成分的含量变化,归纳了软化时果胶甲酯酶(PME)、多聚半乳糖醛酸酶(PG)、果胶裂解酶(PL)和β-半乳糖苷酶(β-GAL)的活性及相应基因表达水平的变化与调控,为采后呼吸跃变型果实保鲜新技术的研发提供理论参考。As an important part of the daily diet, fruits are an important source of vitamin a, vitamin c and dietary fiber. However, fresh fruits are difficult to preserve and will spoil and rot quickly, especially the fruits with respiratory climacteric. This kind of fruits rapidly ripen and soften after the peak of respiration, which not only affects their texture, taste and nutritional value, but also causes the loss of commercial value. The softening process is believed to be related to the degradation of cell wall pectin. Pectin in the cell wall is a kind of complex acidic polysaccharide with D-galacturonic acid as the main component connected by 1, 4-glycosidic bonds, contributing to the adhesion between cells and the mechanical strength of cells. Currently the smooth and hairy region model is the most recognized pectin structure, which consists of four structural domains-homogalacturonans, rhamnogalacturonan Ⅰ, rhamnogalacturonan Ⅱ and xylogalacturonan. Studies have found that the process of fruit ripening and softening is often related to changes in pectin composition. The degree of esterification of pectin and polymerization will decrease. The insoluble protopectin degrades to form soluble pectin and pectic acid, and intercellular adhesion decreases, resulting in softening of the fruit. For example, alkaline soluble pectin is more in the early stage of maturity while water soluble pectin is more in the later stage of maturity in tomato. One of the main reasons for fruit softening is the degradation of pectin, which is catalyzed by specific pectinase including pectin methylesterase(PME), polygalacturonase(PG), pectate lyases(PL) andβ-galactosidase(β-GAL). The main function of PME is to act on the methyl esterified carboxyl group to form methanol and polygalacturonic acid. PG is a key enzyme for the softening of most fruits with respiratory climacteric. Its role is to hydrolyze the glycosidic bond of demethylated polygalacturonic acid residues to produce galacturonic acid. PL degrades pectin polymers directly

关 键 词：采后水果 呼吸跃变 软化 果胶降解 果胶酶 

分 类 号：S66[农业科学—果树学]